West Ham fear James Tomkins could miss the rest of the season with a dislocated shoulder.

The 25-year-old fell awkwardly in training on Thursday and left the field in considerable discomfort. He will have further scans on Friday but manager Sam Allardyce is wary the in-form centre-back will be ruled out for around 10 weeks.

Allardyce only announced at lunchtime that striker Enner Valencia was out after cutting his toe on a broken tea mug.

James Tomkins (right) could miss the rest of the season with a broken shoulder

The in-form West Ham defender suffered the injury during training and left the field in discomfort

'West Ham can confirm that James Tomkins has suffered a dislocated shoulder,' said a club statement. 'The 25-year-old was taken for hospital treatment and will continue to be assessed by the club's medical staff.'

Tomkins' news is compounded as Winston Reid has a hamstring injury and is already ruled out of the Arsenal game while Carl Jenkinson is unavailable as he can't play against his parent club.

The likelihood is that Cheikhou Kouyate will be forced to deputise again.

The likelihood is that Cheikhou Kouyate will be forced to deputise again in defence for West Ham